Question: Simplify the following expression: $7\sqrt{28}$.
First, try to factor a perfect square out of the radical. $= 7\sqrt{28}$ $= 7\sqrt{4 \cdot 7}$ Separate the radical and simplify. $= 7\sqrt{4} \cdot \sqrt{7}$ $= 7 \cdot 2 \cdot \sqrt{7}$ $= 14\sqrt{7}$